1. Field
The present invention relates to an optical information recording medium including a plurality of recording layers and at least one intermediate layer provided between the plurality of recording layers.
2. Description of Related Art
In recent years, research has been carried out on an optical information recording medium including a plurality of recording layers and at least one intermediate layer provided between the plurality of recording layers, in order to record information in multiple layers. JP 2008-293659 A (a related US patent issued under U.S. Pat. No. 5,408,453 A) discloses such an optical information recording medium, in which a guide surface having a guide track (recess for use in tracking) is formed on a substrate, and a spacer layer (intermediate layer) and a recording layer are provided over the guide surface. This document also discloses a method of tracking and recording/reading using different beams (i.e., a guide beam and a scanning beam).